In her Super Bowl ad for SodaStream, Scarlett Johansson promises a “soda that’s better for you and all of us. Less sugar, less bottles.”
Grammar Girl notes that you should use less with “mass nouns” and fewer with “count nouns.” A mass noun, she continues, is something “you can't count individually,” like sugar. A count noun is, well, “something you can count,” like bottles.
Less sugar. Fewer bottles. It’s time to re-cut that ad, SodaStream.